new user ask for advice

What voltage did you connect and how did you connect it?

The external power supply is from an AC adapter whose output is 7.5V/1.0A. It is connected to the power jack.

No there have been several cases on this forum where the power connections are OK but the signal leads are not.

I don't have an extra lead by hand. Is there a way to test it? (Or I can borrow one tomorrow.)

Thank you!